This splits the threads by changing the subject, but you can't combine split threads or split multiple Emails into a different thread, just individual emails. For example, I have multiple emails from the same sender I want to be a thread, but they are combined with other senders that should also be split into different threads. This just splits everything into its own email. If that is what you want, then this will work for you, but it doesn't fit my needs. I only used it for a day so far and will respond again if information gets leaked.